This is a really cool invention that I would love to have. It's called a Cardok and it allows you to stack your cars for parking purposes and then lower one car into the ground. It's something my household could definitely use.

It's great for people who live in big cities and have limited space but I can see it being useful for anyone with multiple cars. We have 4 vehicles in my family but only one can fit in the garage, mainly because we too much crap! Many people find that the garage is used more for storing 'stuff' than cars so your cars are left out in the elements.

Check out the video below of the Cardok. It lowers into the ground to give you double the  parking space, great security, but still looks like just one parking space. It's accessible within 30 seconds.